System for a non-invasive online continuous measurement of phase levels in converters or pyrometallurgical furnaces

• US 6,786,082 B2
• Filed: 05/13/2002
• Issued: 09/07/2004
• Est. Priority Date: 05/13/2002
• Status: Expired due to Fees

• Current Assignee: Escanaba Holdings Incorporated, Saarland Corporation
• Original Assignee: Escanaba Holdings Incorporated
• Inventors: Rojas, Luis Paredes, Garreton, Alfredo Zolezzi
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): HANLEY, JOHN C
• Application Number:
  US10/145,538
• Publication Number:
  US 20030209078A1
• Time in Patent Office: 848 Days
• Field of Search: 73/614.5, 735/90, 732/90.V, 736/27, 266/94
• US Class Current: 73/61.45
• CPC Class Codes: G01N 2291/044 Internal reflections (echoes), e.g. on walls or defects
• CPC Class Codes: G01N 29/032 by measuring attenuation of acoustic waves
• CPC Class Codes: G01N 29/0609 Display arrangements, e.g. colour displays indicating or recording in connection with measuring in general G01D
• CPC Class Codes: G01N 29/222 Constructional or flow details for analysing fluids optoacoustic fluid cells G01N29/2425

Abstract

A non-invasive online system for continuous measurements of phase levels in a converter or pyrometallurgical furnace in smelting and conversion processes, consisting in a electrical signal generator, transducers that convert said electrical signals in mechanical waves placed on the outer end of air blowing tuyeres, coupling means between said system and the shell of the converter, transducers placed in the direction of the axis orthogonal to the phases plane for applying mechanical waves that travel in a transversal direction into the converter, a mechanical waves sensor placed around the external wall of the shell of the converter that receives the reflected signal, a crystal local oscillator, means for the preamplification of the signal, an analogous/digital interface, a means for data acquisition, a means for processing the signals so as to determine the power of the reflected signal and the propagation time of the signal between the moment it is emitted by the transducer and the moment in which the reflected signals are received by the sensor, a memory means to store the continuous values of the phase levels and a visualization means for displaying the continuous values of the phase levels.

Claims

1. A system arranged to be operable with a furnace having mixtures of materials exhibiting different phases, the system comprising:

a blowing tuyere generating an airflow, the tuyere having a furnace duct for transmitting the airflow to the furnace;

an electric signal generator for generating an electrical signal;

at least one transducer converting the electrical signal into mechanical waves, the mechanical waves travelling in the furnace duet together with the airflow in a wave direction which is transversal to the airflow direction along the furnace duct, the mechanical waves being transmitted to the furnace and being reflected by the materials according to their different phases to produce one or more reflected signals;

at least one sensor detecting the one or more reflected signals and generating a corresponding one or more detected signal; and

a first processing element measuring a propagation time of the one or more reflected signals to determine the phase of the mixtures of materials through which the one or more reflected signals have propagated.

2. The system of claim 1, wherein the at least one transducer and the at least one sensor are placed on an external wall of the furnace.

3. The system of claim 1, further comprising

a memory for storing values of the detected signals; and

a display for showing the values.

4. The system of claim 1, wherein the at least one sensor is placed beside or integrated with the at least one transducer.

5. The system of claim 1, further comprising coupling means connecting the electric signal generator and the transducer with the furnace.

6. The system of claim 1, wherein the furnace is a converter.

7. The system of claim 6, wherein the converter is a Teniente Converter (CT).

8. The system of claim 1, wherein the furnace is a pyrometallurgical furnace.

9. The system of claim 1, further comprising:

at least one amplifier, amplifying the one or more detected signal to form one or more amplified detected signals;

an analog/digital interface digitizing the one or more amplified detected signals to form one or more digitized signals; and

a data acquisition circuit acquiring the one or more digitized signals to form acquired data, the acquired data being processed by the processing element.

10. The system of claim 1, wherein the mixtures comprise a metal bath, a slag and gases.

11. The system of claim 1, wherein the mechanical waves are selected from the group consisting of sonic waves, ultrasonic waves and infrasonic waves.

12. The system of claim 1, wherein determination of a level of the phase of the mixtures is based on a corresponding level at which the at least one transducer is positioned.

13. A method for determining phases exhibited by mixtures of materials in a furnace, the method comprising:

transmitting an airflow to the furnace in a duct along a first direction;

generating an electrical signal;

converting the electrical signal into mechanical waves;

transmitting the mechanical waves in the duct together with the airflow along a second direction transversal to the first direction to the furnace, the mechanical waves being transmitted to the furnace and being reflected by the material according to their different phases to produce one or more reflected signals;

detecting the one or more reflected signals and generating a corresponding one or more detected signal; and

measuring a propagation time of the one or more reflected signal to determine the phase of the mixtures of material producing the one or more reflected signals.

14. The method of claim 13, wherein said mechanical waves are selected from the group consisting of sonic waves, ultrasonic waves and infrasonic waves.

15. The method of claim 13, wherein the furnace is a converter.

16. The method of claim 15, wherein the converter is a Teniente Converter (CT).

17. The method of claim 13, wherein the phases are a metal bath, a slag and gases.